Two-temperature refrigerator having special air directing baffle



March 16, 1954 J M. MURPHY TWO-TEMPERATURE REFRIGERATO HAVING SPECIAL AIR DIRECTING BAFFLE Filed March 4, 1952 INVENTOR. John M. Murphy.

Patented Mar. 16, 1954 UNITED STATES TWO-TEMPERATURE REFRIGERATOR HAV- ING SPECIAL AIR DIRECTING BAFFLE John M. Murphy, Oakwood, Ohio, assignor to General Motors Corporation, Dayton, Ohio, a

corporation of Delaware Application March4, 1952, Serial No. 274,691

This invention relates to refrigerating apparatus and more particularly to an improved arrangement of elements within the food storage compartment of a household refrigerator.

It has been found that it is now possible to connect two evaporators in series with a refrigerant liquefying unit and to use the one evaporator for producing below freezing temperatures in a frozen food compartment and to use the other evaporator for maintaining above freezing temperatures in the main food storage compartment. It has also been found possible to defrost the one evaporator located in the relatively high temperature compartment during each ofi cycle without thawing any of the frozen foods in the other compartment. In a system of thi type, it has been found preferable to mount the defrosting evaporator adjacent the upper rear wall of the main food storage compartment and to arrange the frozen food compartment in the upper part of the cabinet. The ceiling of the main food storage compartment then is formed by the bottom of the frozen food compartment and remains fairly cold even during the peak of the defrost portion of the cycle at which time the humidity in the compartment is at its highest with the result that moisture tends to condense on this surface. It is an object of this invention to provide a multiple purpos air directing baflle which not only prevents dripping of this condensate onto the food but which also improves the air flow over the defrosting evaporator so as to facilitate defrosting.

Another object of this invention is to provide an improved condensate drain arrangement.

Further objects and advantages of the present invention wlil be apparent from the following description, reference being had to the accompanying drawings, wherein a preferred form of the present invention is clearly shown.

In the drawings:

Figure 1 is a vertical sectional view partly schematic showing the arrangement of elements within the main food storage compartment of a household refrigerator embodying the invention; and

Figure 2 is a fragmentary front elevational view showing the construction and location of the air directing baffle within the food storage compartment.

Referring now to the drawings for a more detailed description of the invention, the reference numeral ll) designates an insulated refrigerator cabinet having an inner liner l2 forming a food storage compartment l l which is insulated from a machinery compartment located in the lower portion of the cabinet It in accordance with con- 2 Claims. (Cl. 62--103) ventional practice. A conventional access door I8 is provided for the compartment l4 as shown. An insulated frozen food storage chamber 20, having an access door 22, is mounted within the upper portion of the cabient it so that the bottom of the chamber 20 forms the ceiling of the main food compartment l4. Since the construction of the cabinet I 0 and the frozen food chamber 2!! may be varied without departing from the spirit of my invention, and since structure of this type are well known to those skilled in the art they will not be described in greater deta l. For a more complete description of the same, reference is hereby made to co-pending application Serial Number 223,590, filed in the United States Patent Oflice on April 28, 1951.

The frozen food storage chamber 20 and the main food storage compartment M ar refrigerated by means of a pair of evaporators 24 and 25 which are connected in series refrigerant flow relationship with. the refrigerant liquefying apparatu located within the machinery compartment l5. Thus, a, conventional motor-compressor unit 28 withdraws the vaporized refrigerant from the plate type evaporator 26 which is located adjacent the upper rear portion of the food storage compartment I4 and discharges the compressed refrigerant into a conventional condenser all from whence liquid refrigerant flows into the evaporator 2 through a capillary tube of restrictor 32. The outlet of the evaporator 24 is connected to the inlet of the evaporator 26 by means of a line 34. A switch 33 controlled by a thermostat 35 located on the lower corner of the evaporator 26 cycle the compressor and functions to stop the compressor when the temperature of the thermostat falls below -2" F. and restarts the compressor when the temperature of the thermostat reaches 36 F. The construction and arrangement of the evaporators and. I the insulation for the compartments is uch that freezing temperatures are maintained within the chamber 25 at all times whereas the plate type evaporator 26 which is located in the relatively warm food storage compartment 14 will defrost during the off portion of each cycle.

Since the temperatures within the frozen food storage chamber 2!) are maintained considerably below freezing there is a tendency for condensate to collect on the bottom wall 36 of the freezer compartment 20 and the outer surface of the inner door 22. Unless some means is provided for collecting this condensate it will tend to drip onto the food stored within the compartment M. It is not practical to provide a pan for this purpose as the pan would require emptying from time to time.

In the refrigerator shown, a bafiie 40 has been provided which has a forwardly extending lip 42 which collects condensate from the door 22 and which has a horizontally extending portion underlying the frozen food chamber 20 for collecting any'condensate which may drip from the bottom wall 36. The baffle slopes towards the rear whereby condensate flows to the rear edge of the baffie 40 and is then discharged at a point directly over the plate type evaporator'zfi. Acondensate collecting trough 44 is providedfdirectly -beneath the evaporator 26 for collecting the condensate and any defrost water drainingon from the evaporator 26. Thecor'idensate collecting trough 44 does not hold the condensate but mere- 1 1y directs it onto the rear wall ofthe liner l2 as shown in Figure 1, so that the condensate will flow down along the rear wall and moisten'this Wall. Any suitable means may be provided for directing the water into contact with the rear wall.

'For purposes of illustration the wall is shown'with a ri'b' 46 directly beneath the trough44. Some :of

-the coridensate flowing down the' wall will reevaporate into the air so as to maintain a "humid atm'osphere in the food compartment 1 4. 'The overflow or excess conden'satawillrun into a' bot- I tomdrain- 50- provided as shown for discharging =the '-'condensate --into a removable condensate collecting tray 52 located in the machinery cornpartment ifi. The heat 'of the machinerycompartment ldwi'll'tend to vaporize thecondensate therein :with theresult that under 'ordinary' atmosph'eric' conditions it will neverbe necessary toie'mpty the pan 52. The usual vegetable storage means 53 may be provided adjacent thebottomtof' the food compartment I4.

The problem'ofvdefrosting the evaporator- 26 during the off cycle of the-refrigerator presents alproblem 'as-it'is important to have the very 'light coating of ice which forms on the'eva'porator ="26= to -melt promptly during the off cycle, before the'entire'contents of the food'storage compartment 12 warm up excessively. It has been found that the warmesta'ir in" the compartments" tends to collect' in the upper part of the food storage compartment l4 "and it"isthis 'air whichwould 'be' the'most' effective in defrosting -thetevaporator-26 and it is this air which would most'benefit by giving upbeat to the ice on the evaporator so "as to defrost 1 the same. 'It has "been discovered that by arranging'the evaporator 26' and the'bafiie' w'as shown improved aircircu- 'lation takes place which facilitates"the 'defrosting 'operation'of the evaporatonsection i'li.

Thus; it' is seen that'the baffle 40 notcn'ly serves to prevent drippingofuvater 'ontothe foodflbut also serves an important function of facilitatinglthe circulation of warmair over the evaporator and between the evaporator 26 and "the rear" wall of"the liner' i2 so 'as'to facilitate defrosting the rearsidelof' the evaporator '2 6.

The baflie' 4f! serves another useful function in that it" isprovided with "guides 54 for a special I food drawer 56 which is slidable' relative to the bafiie 40. This'foo'ddrawertt; being arranged in the'warmest portionof the food storage compartment, serves as a convenient place for storing cheese, butter and'other similar'ite'ms.

The 'bafile 40 is preferably madeof plastic and'is a'dapted'tobe supported-at its' sides by supports 58 (see' Figure 2) provided on'the" side -walls of the liner i2. Therearcenter'edge of the 'pa'n" is supported by means 'ofa spring clip 60 v'vhic'h engages a'projec'tion 62' 'formed on the battle 40. a The front 1 central portion is further supported by means of a spring latch element 64 carried by the lower wall of the frozen food chamber 20. This spring latch 64 engages a latch engaging element 66 secured to the central front portion of the baflie 40. By virtue of the -above described construction it is possible to make the baffle out of light weight plastic material.

While the form of embodiment of the invention: as herein disclosed constitutes a preferred formfit isto-be understood that other forms might be adopted, as may come within the scope 'of the claims which follow.

{w at isclaime'dis as follows: 1; In a refrigerator having a food storage compartment-and-a frozen food compartment, a first horizontally adjacent the upper rear portion of said food storage compartment, an air directing ebafiie supported beneath said frozen food corn- "pa'rtment so -as to intercept condensate formed on the'lowersurface of said frozen food compartmentand to convey saidcondensate to a point isubstantially' above said plate type evaporator, means for directing the condensate leaving'said plate type evaporator-onto the'rear wall of said food storage compartment,-a-food drawer, and means for slidably supporting said food drawer adjacent the bottom surface of 'said bafile wherebysaidbafiie serves to close the'upper'side of'saiddrawer.

-2. Ina refrigerator having-a foodstorage com partment and a frozen food compartment a first evaporator for-cooling said frozen food compartmentya second evaporator for coolingsaid food storage compartment; said frozen food compartment-'being-dispose'd above-said food storage compartment, 'an outer door for providing access to said compartments,--an inner door for said frozen food compartment, said second evaporator comprising atplatetype evaporator disposed in'a vertical-plane adjacent the upperrear portion of said-foodstorage compartment, a plastic baffle, means for removably supporting said baffle beneath said frozen food compartment so-as to interceptcondensateformed on the lower surface of said frozen food compartment and to conway said condensate to a point substantially above saidplate type'evaporator, and means for directingthe condensate leaving said plate type evap- -orator- --ontoone wallof said food storage compartment,-said means for removably-supporting said baffle including means for engaging both sides and .the front and back central portions thereof.

JOHN M. MURPHY.

References Cited in the file of this patent UNITEns'TATEs PATENTS 

